Azo dye.



UNITED STATES PATENT OFFICE.

JOHANNES JAN SEN AND WILHELM NEELMEIER, OF LEVERKUSEN, NEAR COLOGNE,

GERMANY, ASSIGNORS TO FARBENFABRIKEN VORM. FRIEDB. BAYER 8a 00., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANYE AZO DYE.

No Drawing.

I either nitro-groups or halogens or both nitro-groups and halogens but no sulfonic or carboxylic groups with beta-beta-dioxy-' naphthalenes e. g. 2.3- or 2.6 dioxynaphthalene. V

- The new products possess the valuable property that they can be dyed on wool together with bichromate inthe' same bath. They canalso' be dyed on a chrome mordant or according. to the after-chroming method.

The dyeing in one bath is best done by adding the dye with the bichromate to the bath, entering the wool, boiling, adding acetic acid in small portions and boiling again. In

this way fast black shades are obtained.

ble in water generally with a violet to blue to bluish-black color, and soluble in concentrated sulfuric acid generally with a violet color. They yield upon reduction with stan- 5 nous chlorid and hydrochloric acid aminohenol derivatives and alpha-amino-betata-dioxynaphthalenes.

In carrying out our new process practically we can proceed as follows,'the parts 40 being by weight:

Example :-15.4 parts of 4-nitro-2-aminophenol are diazotized in the usual manner by means of hydrochloric acid and 7 parts of sodium nitrite. The diazo compound is 4 then added to an aqueous solution, which has to .be stirred, until the combination is finished, of 16 parts of 2.6-dioxynaphtha-lene in the calculated quantity of NaOH and containing 200 parts of sodium carbonate.

The'new dyestuffs are dark powders solu- Specification of Letters Patent. Patented Sept. 14, 1909 Application filed February 3, 1909. Serial No. 475,817.

The dyestutt precipitates by acidulation. It is filtered ofi', pressed and dried. It is a dark powder which is soluble in water with a blue and which is soluble in concentrated sulfuric acid with aviolet color. By reduction with stannous chlorid and hydrochloric acid 2.4-diaminophenol and 1-amino-2.6-

dioxynaphthalene are obtained. It dyes wool according to the above described method black shades of good fastness to fulling and to light.

T he. process is carried out in an analogous manner on starting from 2.3-dioxynaphthalene. Other ortho-aminophenol derivatives may be used, such as tchloro-Q-alninophenol, 4.6-dichloro-2-aminophenol, 5-nitro-2-an1inophenol, picraniic acid, 6-chloro-4mitro-2- aminophenol, 6 nitro 4 chloro 2 aminophenol, G-methylA-nitro-2-aminophenol, 4- methyl-6-nitro-2-aminophenol, 2.4-dinitro-3- methyl 6 aminophenol, 5 nitro-4-chloro-2- aminophenol etc.

Having now described our invention and in what manner the same is to be performed.

-what we claim as new and desire to secure by LettersPatent is 1. The herein-described azo dyes derived from dioxynaphthalene having the formula above given combined with ortho amino phenol derivatives that have no sulfonic or carboxylic grou s but contain nitro groups or halogens, an which dyes are after being dried and pulverized, dark powders soluble with stannous chlorid and hydrochloric acid set our hands in the presence of two sub'- 2.4 diaminophenol and 1 amino 7 2.6-di0xyscribing witnesses. naphthalene; and dyeing W001 together with JOHANN ES JANSEN. [L. 8.] bichromate and acid in the same bath black WILHELM NEELMEIER. [L. s.] 5 shades fast to fulling and to light, substan- Vitnesses: v

tially as described. OTTO KbNIG,

In testimony whereof we have hereunto M. WAsHINGmN BRUNSWICK. 

